DE 299 08 490 U1 indicates a holding system for various types of plug connectors, in which holding system lateral parts, which can be latched onto a base plate with a fixed holder and a displaceable holder, can be fastened to a first insulating body which can have different lengths. Holding systems for plug connectors are also known, in which a base plate holding the plug connector is held on a contact-insert holding arrangement by means of screws, although in these systems a tool is always needed for fastening purposes.